package com.shangtianzhu.gulimall.product.annotation;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import java.util.HashSet;
import java.util.Set;

/**
 * @author rongpeng.yao
 * @version 1.0
 * @description: TODO
 * @date 2021/9/3 16:17
 */
public class ListValueConstraintValidator implements ConstraintValidator<ListValue,Integer> {

    private Set<Integer> set=new HashSet<>();
    /**
     * Initializes the validator in preparation for
     * {@link #isValid(Object, ConstraintValidatorContext)} calls.
     * The constraint annotation for a given constraint declaration
     * is passed.
     * <p>
     * This method is guaranteed to be called before any use of this instance for
     * validation.
     * <p>
     * The default implementation is a no-op.
     *
     * @param constraintAnnotation annotation instance for a given constraint declaration
     */
    @Override
    public void initialize(ListValue constraintAnnotation) {
        // 获取后端写好的限制 // 这个value就是ListValue里的value，我们写的注解是@ListValue(value={0,1})
        int[] value = constraintAnnotation.value();
        for (int i : value) {
            set.add(i);
        }
    }

    /**
     * Implements the validation logic.
     * The state of {@code value} must not be altered.
     * <p>
     * This method can be accessed concurrently, thread-safety must be ensured
     * by the implementation.
     *
     * @param value   object to validate
     * @param context context in which the constraint is evaluated
     * @return {@code false} if {@code value} does not pass the constraint
     */
    @Override
    public boolean isValid(Integer value, ConstraintValidatorContext context) {
        return set.contains(value);
    }
}
